Various apparatus and systems have attempted to generate and store power through the use of the motion of the tide or other periodic rising and falling of a body of water. One set of systems uses the horizontal flow of the wave power to rotate a generator. Another set of systems uses the vertical movement of the tide to generate power. In this second system for generating power or energy from the rise and fall of a body of water, i.e. —due to tidal movement, it is desirable to have a means for storing energy at peak periods of generation for use during periods when demand exceeds generation, i.e. at slack tide, in order that a continuous flow of energy can be provided.
One method is the use of weights that are lifted to store energy when power generation exceeds demand, and allowed to drop to generate extra power when demand exceeds the rate of power generation from the fluid level dependent system. Another method of deriving energy from the rise and fall of a body of water consists of a float adapted to move substantially in a vertical plane in response to the rise and fall of the body of water. A cylinder has a piston adapted for vertical movement relative to the cylinder in response to the rise and fall of the float with the body of water, in a manner to apply force to fluid in a chamber of the cylinder, the force being applied alternately to opposed chambers of the cylinder, means for converting force applied to the fluid to energy, and means responsive to energy demand for storing energy converted from force applied to the fluid and for converting stored energy to force applied to the fluid.
Unfortunately, there are deficiencies in traditional horizontally-oriented tide activated power systems including maintenance concerns due to significant seawater acting on the generator. Furthermore, conventional tide activated power systems are inefficient for at least one of numerous factors. These factors include inefficiencies in generating power from horizontal flow of the water that moves in both directions relative to the generator, coupling to cylinders at different heights, or the coupling of multiple smaller units for efficiency.